The twist drill is the most widely used drilling tool for drilling into solid material and bores having a diameter up to approximately 18 mm. The material used in manufacturing twist drills is alloyed tool steel, high-speed steel, and hard metal. If needed, the drill can be coated with a wear-reducing layer of e.g. titanium nitride. Wear occurs mainly in the vicinity of the drill tip in the region of the main cutting edge and at the guide chamfer. In order to eliminate the wear, it has been hitherto known to re-grind the drill at the corresponding flanks. In this, it is found to be disadvantageous that the drill becomes shorter during the grinding operation. In order to avoid this disadvantage, it is further known (DE-C-37 09 878) that the cutting part consists of a base body connected to the drill shank as one part and an exchangeable tip connected to the drill tip as one part, which are connectable to each other in a form- and friction-fitting manner at an axial separation point.
Based on this, it is the object of the invention to improve the known drilling tool of the type described above such that a reduction of wear and an improvement of the drilling quality can be obtained by simple productional measures.